Little League is built on the idea that every kid plays. That principle shows up in the rulebook as “mandatory play,” and understanding it is the difference between a lineup that is fair and one that is technically illegal.
The minimum: six outs and one at-bat
In the regular season, Little League Regulation IV(i) requires every rostered player present at the game to play a minimum of six consecutive defensive outs and to bat at least once. “Consecutive” is the key word — you cannot split those outs across the game. Six consecutive defensive outs is roughly two full innings in the field.
Continuous batting order
Most Little Leagues use a continuous batting order, where every present player bats in a fixed rotation whether or not they are currently in the field. This automatically satisfies the at-bat requirement and removes a whole category of substitution mistakes.
The arithmetic trap
With a deep roster and a six-inning game, the bench has to move every inning to get everyone their outs. Coaches get into trouble by benching weaker fielders early and planning to “catch them up” late — then running out of innings. Plan the rotation before the first pitch.
Tournament play is stricter
In All-Star and tournament play there are no local modifications, and mandatory-play misses can be protested. With 13 or more players in uniform, each must bat once; with 12 or fewer, each must play six consecutive defensive outs and bat once.
Our Little League builder tracks all of this as you set the field, warning you before a player is headed for too much bench time. Always confirm your own league’s house rules, which can be stricter than the minimum.